Such brakes are widely used in industrial plants. They are usually made as disk or drum brakes. Here, two brake lever arrangements form a brake caliper which is provided with two brake shoes (brake pad or lining, brake pad or lining support), and the brake body (usually a disk or drum) to be slowed down runs between said brake shoes. In order to brake, the brake caliper and thus also the brake shoes are closed via a lever mechanism, the brake shoes exert a brake force on the brake body, and the rotary motion thereof is inhibited or stopped by the resulting frictional forces.
The basic set-up of such brakes is similar. In the case of an upright brake, the lower (first) end of each of the two brake levers is swivel-mounted at a distance relative to each other on a basic frame (support). At the upper (second) end thereof, they are coupled to one another via an adjusting lever, a rocker arm and an adjusting rod. The adjusting lever moves synchronously with the rocker arm and, at one end, is connected in articulated fashion to the upper end of a brake lever and, at the adjusting leg thereof, is articulated by a brake releasing device or a and a brake spring, which are also mounted in articulated fashion to the support at the opposing (lower) end thereof.
The rocker arm coupled to the adjusting lever is coupled in articulated fashion via a leg end to an end of the adjusting bar which, with the other end thereof, is articulated on the upper end of the other brake lever. In order to brake, the adjusting lever is pulled down via the brake releasing device and/or via the brake spring, the associated tilting movement of the rocker arm which engages the adjusting bar reduces the distance between the two ends of the brake lever and in so doing performs the caliper movement which joins the brake levers or brake pads, thus acting on the brake body.
In order to release the brake, the releasing device or the brake releasing device forces the adjusting lever leg upwards, thus pushing the two brake levers apart so as to conduct an opening/releasing brake lever caliper movement. The brake pads are removed from the brake body which is released.
During the operation, the brake pads and, to lesser degree, the brake bodies wear off. Without compensation, this will increase the braking distances which can change the response times and brake characteristics (brake force). In order to compensate for this wear, the adjusting rod is provided with a readjusting mechanism which via a stop-free run-spindle arrangement reduces the length of the adjusting rod in accordance with wear, as a result of which the braking distances remain approximately constant.
Another problem of these lever brakes is that tilting forces are applied by the adjusting elements (brake releasing device and brake spring) when the brake is released. As a result of said tilting forces, the two brake levers can swivel/tilt accordingly in one direction while a brake pad abuts and rubs against the brake body.
In order to solve this problem there are (readjustable) stops which take effect between a brake lever and a basic frame and shall prevent this tilting—i.e. center the released brake levers to the brake body. There are stops which are manually readjusted in accordance with wear from time to time or also those which have a readjusting mechanism that adjusts itself automatically in an updating fashion—i.e., adapts to the wear-related change in the brake lever position. Such stop mechanisms are known from DE 196 09 764 A1, for example. They use e.g. adjustment cranks and/or a linear free run that can be telescoped, all of which take effect between the brake levers and the support (frame). Such mechanisms are comparatively complex structure-wise and can require extensive maintenance.
Therefore, the object is to provide an improved and in particular also simplified centering mechanism which prevents tilting of the brake lever mechanism.